RETINA Flashcards
- Name layers of retina!
- What is diabetic retinopathy?
- RPE
layer of rods and cones
External limiting membrane
Outer nuclear layer
Outer plexiform layer
Inner nuclear layer
Inner plexiform layer
Ganglion cell layer
Nerve fibre layer
Internal limiting membrane - It is a progressive dysfunction of retinal vasculature secondary to chronic hyperglycemia.
Conventional classification of Diabetic retinopathy
-
Background diabetic retinopathy
Micro aneurysms
Retinal edema
Hard Exudates(lipoproteins and lipid filled macrophages)
Superficial and dot blot hemorrhages
Pre proliferative stage
Venous dilation and beading.
Cotton wool spots (occlusion of pre capillary arterioles swelling of nerve fibers)
Intra retinal microvascular abnormalities (IRMA)
Proliferative stage
Retinal neovascularization
Pre retinal hemorrhage
Vitreous hemorrhage
Tractional retinal detachment
Diabetic maculopathy
Focal maculopathy (focal capillary leakage and well circumscribed retinal thickness)
Diffuse maculopathy (extensive capillary leakage and retinal thickening)
Advanced diabetic eye disease
Persistent vitreous hemorrhage
Tractional retinal detachment
Neovascular glaucoma
Burnt out stage
Vascular component is regressed
Fibrous component is left behind
Early Treatment Diabetic Retinopathy study classification
1.Mild non proliferative diabetic retinopathy
Micro aneurysms only
2.Moderate NPDR
micro aneurysms
Venous changes
Retinal hemorrhage
Exudates
Cotton wool spots
3.Severe NPDR
Any one of this 4…2…1 rule
Hemorrhage in all 4 quadrants
Venous beading in 2 or more quadrants
IRMA in one or more quadrants
4.Very severe NPDR
2 or more of the criteria for severe NPDR
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Proliferative Diabetic Retinopathy
New Vessels elsewhere
New Vessels on the disc
6.Diabetic Macular edema
Focal and diffuse maculopathy
-
Advanced diabetic eye disease
Persistent vitreous hemorrhage
Tractional retinal detachment
Neovascular glaucoma
Hypertensive retinopathy
KEITH WEGNER AND BARKER CLASSIFICATION for changes in old age
Grade 1
Generalized arteriolar narrowing
Broadening of arteriolar light reflex
Concealment of vein by arteriole
Grade 2
Above changes plus
Focal arteriolar narrowing
Sallus sign deflection of vein at AV crossing
Grade 3
Above changes plus
Retinal edema, hemorrhage,Exudates and cotton wool spots
Copper wire appearance of arterioles
Bonnet sign banking of vein distal to AV crossing
_Gunn sign_Tapering of veins on either side of crossings
Grade 4
Above changes plus
Optic disc edema
Silver colour appearance of arterioles
Scheie classification of hypertensive retinopathy for young age
What is malignant hypertension?
Grade 1
Generalized arteriolar narrowing
Grade 2
Above changes plus
Focal arteriolar narrowing
Grade 3
Above changes plus
Retinal flame/splinter hemorrhage
Retinal edema
Cotton. Wool spots
Hard Exudates
Grade 4
Above changes plus Optic disc edema
When hypertensive retinopathy causes bilateral optic disc edema(papilledema), the systemic hypertension is called malignant hypertension.
A 60 years old man presented to emergency dpt with complaints of sudden loss of vision. On fundoscopy you noticed absent venous pulsations ,dilated veins,dot blot/flame shaped hemorrhages were present in all four quadrants(tomato splashed appearance) along with cotton wool spots. There is mild disc edema. What is your dx?
How would you treat this man?
What complications can develop in this patient?
CRVO.
Non ischemic if FFA shows good capillary perfusion
Ischemic if FFA shows capillary non perfusion.
Branch retinal vein occlusion will have hemorrhages in one quadrant only.
Hemi retina vein occlusion will have hemorrhages involving lower half of retina.
Treatment
Return of vision occurs in 50% of cases.
Control HTN,DM and give anti platelet therapy.
Intra vitreal VEGF and steroids are indicated if visual loss is more than 6/9 or if macular thickness on OCT is greater than 250 microns
Complications
Cystoid macular edema
Non ischemic can convert to ischemic
Rubeosis iridis(iris neovascularization) treated by pan retinal photocoagulation
In branch/hemi retinal vein occlusion,when visual acuity is 6/9 or better no intervention is needed.
If visual acuity is 6/12 then intravitreal VEGF,laser photocoagulation and intravitreal steroid is indicated.
A 45 years old female presented to ER with complaints of sudden vision loss . On examination fundus shows pale retina and cherry red spot ,cattle tracking and narrowing of retinal arteries . FFA shows delay in arterial filling and electroretinography shows diminished b wave .
What is your dx?
Treatment?
Central Retinal artery occlusion.
Branch artery occlusion will show sectoral vision loss.
Treatment
Reduce IOP by IV acetazolamide and mannitol.
Ocular massage to dislodge emboli.
Sublingual isosorbide dinitrate.
IV Methylprednisolone
Breathing high O2 may relieve vasospasm.
1.In which retinal disease does Drusen(lipid deposits bw RPE and Bruchs membrane) and RPE abnormalities occur?
- Two types of this disease?
1.Age Related Macular Degeneration.
- **Dry/atrophic/non neovascular ARMD*(most common form 90%)
Atrophy of RPE, Photoreceptors and choriocapillaries occur.
TTT
Amsler grid testing of vision
Address risk factors e.g DM,HTN
Use antioxidants
Exudative/wet/neovascular ARMD (10%)
Sudden Central vision loss occurs and scotoma forms.
Choroidal neovascularization bleed and cause hemorrhage and exudation.
Treatment
Intravitreal VEGF
Intravitreal steroids
Argon laser photocoagulation
Photodynamic therapy
Surgery….sub macular surgery and macular translocation
Types of retinal detachment?
- Separation of sensory retina from RPE by sub retinal fluid.
Two main types
Rheugmatogenous retinal detachment
Occurs due to full thickness break in sensory retina
Non rheugmatogenous RD
Include
Exudative and tractional RD.
Exudative RD Occurs due to damage to RPE ,which allows fluid from choriocapillaries to leak into sub retinal space.
Tractional RD pull on sensory retina by contracting vitreorerinal membrane.
- How would you treat rheugmatogenous or primary retinal detachment?
- How would you treat tractional RD?
- How to treat exudative RD?
1.localize the break
Sub retinal fluid drainage
Choriorerinal opposition by scleral buckling,pneumatic retinopexy in break in upper retina and pars plana vitrectomy with internal tamponade.
- Pars plana vitrectomy
And internal tamponade - control underlying conditions e.g HTN.
A 15 year old boy presents to OPD with complaints of night blindness and tunnel vision during day time. His dark adaptation time is prolonged. Perimetric examination shows ring scotoma. His contrast sensitivity is affected too. On fundus examination, attenuation of retinal blood vessels occur and pigmentary bony specules occur . What is your dx?
How would you treat this patient?
Retinitis pigmentosa.
A hereditary degenerative disorder characterized by atrophy of RPE AND RODS causing night blindness,visual field constriction and night blindness.
2.there is no specific TTT. Use antioxidants vitamin A and E.
Use dark sunglasses
Low vision aids.
A 2 years old child presented to opd with swelling and proptosis of one eye. He had positive leukocoria on direct ophthalmoscopy in the normal eye. There are pearly white deposits on the mass. Histology reveals flexner winterstainer rosettes and fluorettes. What is your dx?
What are the treatment options?
- Retinoblastoma
If less than half of retina is involved and optic nerve is not involved we do chemotherapy, photocoagulation, cryotherapy, brachytherapy.
If more than half retina or optic nerve is involved we do enucleation surgery.
